434 
BLUE-BLACK WRITING-INK. 
Second object .—To discover a means of preserving the active principles of the pancreas 
in a form suitable for experiment in the laboratory, and for administration as a remedial 
agent. 
The properties of the paucreas can be extracted from the tissue of the gland by means 
of water. This watery fluid putrefies very rapidly. It has an acid reaction, a deep 
yellow colour, coagulates largely by boiling, leaving the colour of the fluid unaltered. It 
may be precipitated by lead solution, and decomposed again by sulphuretted hydrogen. 
When this watery fluid is evaporated, it forms a syrupy extract, which is highly 
hygroscopic and very difficult to dry. With great care and trouble, it may be dried. 
For general purposes, the drying is greatly facilitated by adding a dry absorbing- 
powder, such as powdered malt. For experimental purposes, it may be used in its pure 
undried state of syrupy extract, but must in that case be used fresh. In the dry state, 
either pure or mixed with malt-dust, it may be kept good for an indefinite length of 
time, if protected from moisture in a well-closed bottle. This extract of the pancreas, 
containing the active principles of the pancreas in the highest degree of efficiency, 
whether fluid or powdered, I call “ pancreatine.” This term is used only for convenience ’ 
sake, and must in no way be understood to signify that the property possessed by it is 
single. All attempts to isolate the several properties of the pancreas into separate pro¬ 
ducts have failed, no one of such products having been found to possess in perfection the 
property of acting upon fat in the manner described in this paper as peculiar to the pan¬ 
creas. By the term “ pancreatine,” then, I desire to represent the entire properties of 
the pancreas extracted in a convenient form for keeping, for experiment, and for ad¬ 
ministration as a remedial agent. 
One part of the pure pancreatine dried, without mixture with malt-dust, will digest 
at least sixteen parts of lard, and enable it to form a thick creamy emulsion, with about 
100 parts of water. The emulsion thus formed presents in every respect the characters 
and qualities of the emulsion produced by the fresh pancreas already described. In this 
way, therefore, the active principles of the pancreas may be obtained and preserved in 
a form suitable for experiment in the laboratory and for administration as a remedial 
agent. 
The third object of my investigations has especially occupied my attention in a long 
series of experiments at the Royal Hospital for Diseases of the Chest. Full details of 
these and of the results obtained have been published from time to time, during the last 
four years, in the medical journals; I shall not, therefore, occupy the time of the society 
with any account of them in this paper .—Proceedings of the Royal Society. 
BLUE-BLACK WRITING-INK. 
A correspondent has sent us the following recipe for a blue-black writing-ink, wliich, 
he says, answers very well for a copying-ink:— 
Take of Aleppo Galls, bruised.ounces. 
Cloves, bruised .^ ounce. 
Sulphate of Iron.l| „ 
Sulphate of Indigo, in the form of a slightly- 
acid paste (Sulphindylate of Potash ?) . li „ 
Sulphuric Acid.35 minims. 
Rain Water, cold.40 ounces. 
Macerate the galls and cloves in 20 ounces of the water for a week ; decant the liquor, 
and add to the residue of the solid ingredients 10 ounces of the water, with which con¬ 
tinue the maceration for four days ; then decant as before, and repeat the maceration with 
the remaining 10 ounces of water for another period of four days. Mix now the whole 
of the liquors, recovering from the galls all that can be obtained by squeezing them in a 
cloth, and afterwards filter. To this add first the sulphate of iron, then the sulphuric 
acid, and lastly the indigo paste. Care must be taken that the indigo does not contain 
much free acid. 
